Battery Disconnect Safeguard

ABSTRACT

In embodiments, a mobile device includes a primary battery as a power source to power components of the mobile device, and includes a secondary battery as an additional power source to power the components of the mobile device. A sensor is implemented to detect a free-fall of the device that indicates an impending secondary battery disconnect event due to the mobile device being dropped. A battery controller is implemented to receive a sensor input of the detected free-fall from the sensor. The battery controller can then switch from the secondary battery to the primary battery as the power source based on the detected free-fall of the mobile device. The battery controller can switch back from the primary battery to the secondary battery as the power source based on a lack of acceleration of the mobile device.

RELATED APPLICATION

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 14/604,378 filed Jan. 23, 2015 entitled “BatteryDisconnect Safeguard”, the disclosure of which is incorporated byreference herein in its entirety.

BACKGROUND

Portable devices, such as mobile phones, tablet devices, digitalcameras, and other types of computing and electronic devices cantypically run low on battery power, particularly when a device isutilized extensively between battery charges. Some mobile devices aredesigned to attach and/or incorporate a secondary battery as analternate or additional power source to the primary battery that powersa device. However, these secondary batteries can be susceptible tovarious external and environmental factors, causing a momentary (orlonger-term) loss of power which leads to device shutdown. For example,a mobile device may be operating and powered by a secondary battery whenthe device is dropped. The resulting impact from the device beingdropped may momentarily or permanently dislodge the battery connectioncausing device shutdown. Further, a secondary battery that is powering adevice may be susceptible to moisture exposure, which can short-out thebattery contacts causing the device to shut down while the device isbeing powered by the secondary battery.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of battery disconnect safeguard are described with referenceto the following Figures. The same numbers may be used throughout toreference like features and components that are shown in the Figures:

FIG. 1 illustrates an example system in which embodiments of batterydisconnect safeguard can be implemented.

FIG. 2 further illustrates examples of a mobile device and varioussecondary battery configurations in which embodiments of batterydisconnect safeguard can be implemented.

FIG. 3 illustrates an example method of battery disconnect safeguard inaccordance with one or more embodiments related to maintainingcontinuous power for a mobile device when subject to an impendingsecondary battery disconnect event due to an impact from the devicebeing dropped.

FIG. 4 illustrates another example method of battery disconnectsafeguard in accordance with one or more embodiments related tomaintaining continuous power for a mobile device when subject to animpending secondary battery disconnect event due to an impact from thedevice being dropped.

FIG. 5 illustrates various components of an example device that canimplement embodiments of battery disconnect safeguard.

DETAILED DESCRIPTION

Embodiments of battery disconnect safeguard are described, such as forany type of mobile device that may be implemented with both a primarybattery and a secondary battery as an additional power source to powercomponents of the device. For example, a mobile phone typically includesa primary battery that is integrated within the housing of the deviceand has a reliable, protected battery connection to power the device.The mobile phone may also include a secondary battery that can beswitched-in as an additional power source to the primary battery topower the components of the mobile device. In various implementations, asecondary battery can be integrated within a mobile device, such aswithin the housing of the device, or integrated in a removable housingcover of the device, such as integrated in the removable battery coverof the device housing, or integrated in the removable protective coveror case for the whole device. Alternatively, a secondary battery may beconnected to battery contacts that are integrated in the housing of themobile device, such as for a secondary battery that clips onto orattaches externally to the device, or the secondary battery can beexternal to the device and connected by a cable or any other type ofwired connection.

In any of the various secondary battery implementations, the batteryconnection of the secondary battery is susceptible to beinginadvertently disconnected from the mobile device, such as due tovarious external or environmental factors as described above. Forexample, a user may drop a mobile phone and the resulting impact of thedevice with the ground or other hard object may momentarily orpermanently dislodge the battery connection, causing device shutdown inan event that the secondary battery is powering the device. Similarly, asecondary battery that is powering a device may be susceptible tomoisture exposure, which can short-out the battery contacts causingdevice shutdown or permanent damage to the device. A secondary battery,or at least the battery contacts, may be sealed or protected fromenvironmental elements by a gasket or similar-type seal. However, adamaged seal or gasket can lead to moisture ingress, exposing thebattery and/or the battery contacts to moisture that may short-out thebattery.

The described aspects of battery disconnect safeguard provide that amobile device being powered by a secondary battery as an alternate oradditional power source will maintain continuous power to operate thedevice, rather than possible device shut-down caused by an impendingsecondary battery disconnect event due to the mobile device falling, ormoisture exposure shorting-out the battery connections. Although notlikely to damage the device when power is suddenly interrupted, theunexpected loss of power results in a poor user experience, and it isgenerally preferable to maintain device power in any operation orstandby mode.

In one aspect of battery disconnect safeguard, an accelerometer isimplemented to detect acceleration of the mobile device, which indicatesthat the device has been dropped and is falling with an impending impactthat may interrupt device power. A battery controller is implemented toreceive the detected acceleration as a sensor input from theaccelerometer, and then controller logic initiates a battery switchcircuit to switch from the secondary battery to the primary battery asthe power source based on the detected acceleration of the mobiledevice. Additionally, a mobile device may be implemented with contactsensors that detect touch contact with the device, and the batterycontroller switches from the secondary battery to the primary batterybased on both the detected acceleration of the mobile device and nodetected touch contact with the mobile device. A detected touch contactwith the mobile device is an indication that the device has not beendropped and/or is not falling.

In another aspect of battery disconnect safeguard, a moisture detectoris implemented to detect moisture proximate the battery connection ofthe secondary battery in the mobile device, which may then result in aloss of device power or device damage if the secondary batteryshorts-out. The battery controller is implemented to receive thedetected moisture as a sensor input from the moisture sensor, and thenthe controller logic initiates the battery switch circuit to switch fromthe secondary battery to the primary battery as the power source basedon the detected moisture. The battery controller can also be implementedto monitor the charge level of the primary battery, and maintain atleast a minimum charge level of the primary battery to enable the switchfrom the secondary battery to the primary battery as the power source inthe event that the controller logic of the battery controller initiatesthe battery switch.

While features and concepts of battery disconnect safeguard can beimplemented in any number of different devices, systems, environments,and/or configurations, embodiments of battery disconnect safeguard aredescribed in the context of the following example devices, systems, andmethods.

FIG. 1 illustrates an example mobile device 100 in which embodiments ofbattery disconnect safeguard can be implemented. The example mobiledevice 100 may be any type of mobile phone, tablet device, digitalcamera, or other types of computing and electronic devices that arebattery powered. In this example, the mobile device 100 has a primarybattery 102 as the power source to power various components of thedevice. Additionally, the mobile device 100 has a secondary battery 104that is an additional power source to power the components of thedevice, and generally, the secondary battery is removable from thedevice. The various components of the mobile device 100 are shown in aside view 106 of the device, and also in a block diagram forillustrative discussion. In the example side view 106, the secondarybattery 104 is shown integrated within the housing 108 of the mobiledevice 100.

FIG. 2 illustrates various examples 200 of additional secondary batteryconfigurations in which embodiments of battery disconnect safeguard canbe implemented. As shown at 202, the secondary battery 104 may beexternal to the mobile device 100 and connected by a cable 204 or anyother type of flexible and/or wired connection. Alternatively as shownin a side view 206, the secondary battery 104 may be integrated in aremovable housing cover 208 of the mobile device 100, such as integratedin the removable battery cover of the device housing. Alternatively asshown in another side view 210, the secondary battery 104 may clip ontoor attach externally to the mobile device 100, and is connected tobattery contacts that are integrated in the housing 108 of the mobiledevice. Alternatively as shown in another side view 212, the secondarybattery 104 may be integrated in a protective case or cover 214 for themobile device 100, and the battery connection is configured on theexternal surface of the housing 108. When the protective cover with theintegrated battery is positioned on the housing, the battery contacts inthe protective cover contact the pads on the housing to create thebattery connection with the device.

The mobile device 100 includes a battery controller 110 that isimplemented to switch between the primary battery as the power source topower the components of the device, and the secondary battery as thealternate or additional power source to power the components of thedevice. As shown in the side view 106, the primary battery 102 isconnected to the battery controller 110 via a battery connection 112.Similarly, the secondary battery 104 is connected to the batterycontroller 110 via a battery connection 114. In embodiments, the batterycontroller 110 can be implemented with hardware components, which aregenerally time-sensitive and respond faster than a softwareimplementation to safeguard the mobile device from a secondary batterydisconnect event, and sudden loss of power.

Additionally, the mobile device 100 can be implemented with variouscomponents, such as a processing system and memory, as well as anynumber and combination of differing components as further described withreference to the example device shown in FIG. 5. As an alternative tohardware components, the battery controller 110 can be implemented as asoftware application or module, such as executable software instructions(e.g., computer-executable instructions) that are executable with aprocessing system of the device to implement embodiments of batterydisconnect safeguard. The battery controller 110 can be stored oncomputer-readable storage memory (e.g., a memory device 116), such asany suitable memory device or electronic data storage implemented in themobile device. In practice, the battery controller 110 may beimplemented in software as part of an operating system of the mobiledevice. Additionally, a separate microcontroller may be implemented toprocess the battery controller 110 as software for a time-sensitive,quick response to a secondary battery disconnect event.

In this example, the battery controller 110 includes a battery switchcircuit 118 that switches between the primary battery 102 and thesecondary battery 104 as the power source to power the components of thedevice. The battery controller 110 also includes controller logic 120that controls the battery switch circuit 118, which may be based on oneor more sensor inputs 122 as described further below. As with thebattery controller 110, the controller logic 120 may be implemented inhardware, software, or as a combination thereof.

The mobile device 100 also includes one or more sensors 124, which maybe implemented as any one or combination of an accelerometer, gyro,touch contact sensors, a moisture detector, temperature detector, and/orany other type of environmental condition sensors. In aspects of batterydisconnect safeguard, a sensor 124 is implemented as an accelerometer126 to detect acceleration of the mobile device 100, which can indicatean impending secondary battery disconnect event due to the mobile devicefalling. For example, a detected acceleration of approximately 9.8 m/s²(meters per second squared) indicates a device falling based ongravitational acceleration. In practice, the accelerometer 126 can beimplemented to detect a range of acceleration, such as an approximaterange between 9.75 m/s² and 9.85 m/s², which can then be interpreted asa device falling. Alternatively or in addition, a sensor 124 isimplemented as a moisture detector 128 to detect moisture proximate thebattery connection of the secondary battery 104 in the mobile device100, which can indicate an impending secondary battery disconnect eventdue to the secondary battery shorting out.

In an aspect of battery disconnect safeguard, the battery controller 110is implemented to receive a sensor input 122 of detected acceleration ofthe mobile device 100 from the accelerometer 126 (e.g., a sensor 124),and then initiate a switch from the secondary battery 104 to the primarybattery 102 as the power source based on the detected acceleration ofthe mobile device. As described above, an acceleration of the mobiledevice 100 can indicate that the device has been dropped and is falling,in which case the impending impact with the ground or other hard objectmay dislodge the battery connection of the secondary battery, causing adevice shutdown in an event that the secondary battery is powering thedevice. Similarly, the detected acceleration of the mobile device 100may indicate that the device has been thrown, in which case the devicemay impact a hard surface and/or then the ground, also resulting in adisconnect of the secondary battery connection.

As an additional safeguard, the sensors 124 of the mobile device 100 mayinclude one or more contact sensors (e.g., device perimeter touchsensors) configured to detect touch contact with the mobile device, suchas when a user holds the device. If the battery controller 110 receivesa sensor input 122 as detected acceleration of the device from theaccelerometer 126, yet a contact sensor (e.g., a sensor 124) detectsuser touch contact with the device, the controller logic 120 candetermine that an impact is not imminent or pending, such as from thedevice falling or being thrown. For example, the accelerometer 126 maydetect acceleration of the mobile device 100 in a vehicle while one ormore contact sensors detect user touch contact with the device,indicating that the device is not falling. Alternatively however, thecontroller logic 120 of the battery controller 110 is implemented toinitiate the battery switch circuit 118 switching from the secondarybattery 104 to the primary battery 102 based on both detectedacceleration of the mobile device 100 and no detected touch contact withthe device. It should be noted that the battery controller 110 is alsoimplemented to initiate the battery disconnect safeguards if the mobiledevice is in a standby mode, such as if the display is turned off, butthe device is still otherwise powered and operational.

The battery controller 110 is also implemented to monitor a charge levelof the primary battery 102, and maintain at least a minimum charge levelof the primary battery to enable a switch from the secondary battery 104to the primary battery 102 as the power source. Generally, the primarybattery 102 will serve as a back-up power source with a minimum charge(such as 5%) for the short period of time needed to support a switchfrom the secondary battery 104 to the primary battery 102 during animpending disconnect of the secondary battery connection. Alternatively,a small cell battery or capacitor could be utilized as the back-up powersource in the mobile device. When a fall and/or bounce of the mobiledevice 100 has completed, as determined based on a significant decreasein device acceleration (e.g., approximately zero acceleration), thebattery controller 110 can initiate switching back to the secondarybattery 104 from the primary battery 102 as the power source of thecomponents of the device. In an event that the battery controllerdetects the primary battery 102 has been depleted of power withoutmaintaining at least a minimum charge, then the battery controller 110is implemented to not initiate the switch from the secondary battery 104to the primary battery 102 as the power source.

In implementations of battery disconnect safeguard, a log of detectedacceleration data can be maintained as a record of the deviceacceleration. For example, the accelerometer 126 (e.g., a sensor 124)may be implemented with a sensor buffer 130 to maintain the log data ofthe detected acceleration. Alternatively or in addition, the log datacan be streamed to the memory device 116 of the mobile device 100 tomaintain the log data as a record of the detected acceleration of thedevice.

In another aspect of battery disconnect safeguard, the batterycontroller 110 is implemented to receive a sensor input 122 of moisturethat is detected proximate the battery connection of the secondarybattery 104. The mobile device 100 includes the moisture detector 128that is implemented to detect moisture in the device and/or proximatethe battery connection of the secondary battery 104. The moisturedetector 128 can be implemented to detect moisture on a circuit boardthat implements the battery controller, at the battery connection of thesecondary battery itself, and/or proximate the battery connection. Inimplementations, the battery connection may be configured on theexternal surface of the housing, and when the protective cover with anintegrated battery is positioned on the housing, the battery contacts inthe protective cover contact the pads on the housing to create thebattery connection with the device. As described above, moisture ingressmay occur due to a damaged gasket or seal that is designed to preventthe battery and/or battery contacts from moisture exposure that mayshort-out the battery. For example, the mobile device 100 may fall intoa puddle of water, which leads to moisture proximate the batterycontacts of the secondary battery. The battery controller 110 canreceive a sensor input 122 of detected moisture from the moisturedetector 128 (e.g., a sensor 124), and then initiate a switch from thesecondary battery 104 to the primary battery 102 as the power sourcebased on the detected moisture.

In aspects of battery disconnect safeguard, other environmental factorsmay also be considered, such as exposure of the secondary battery tocold or heat outside of an expected operating temperature range. Forexample, a secondary battery that is configured external to the mobiledevice may become overheated when exposed to direct sunlight, such asthe external wired secondary battery shown at 202 (FIG. 2), or thesecondary battery that is connected to the external housing of themobile device as shown in the side view 210. Similarly, a secondarybattery may overheat due to the external temperature and while chargingthe battery.

Additionally, a secondary battery may not perform to power the mobiledevice 100 if left in a cold environment, such as outside or in avehicle. In any of these scenarios, the battery controller 110 canreceive a sensor input 122 from a temperature sensor (e.g., a sensor124), and then the controller logic 120 can initiate a switch from thesecondary battery 104 to the primary battery 102 as the power sourcebased on the detected temperature and/or operating condition. Assimilarly noted above, the controller logic 120 of the batterycontroller 110 can initiate the battery switch circuit 118 to switchback to the secondary battery 104 from the primary battery 102 as thepower source of the components of the mobile device 100 when themoisture is no longer detected (e.g., has dried) and/or when thetemperature and other conditions return to an expected operating range.

Example methods 300 and 400 are described with reference to respectiveFIGS. 3 and 4 in accordance with implementations of battery disconnectsafeguard. Generally, any services, components, modules, methods, and/oroperations described herein can be implemented using software, firmware,hardware (e.g., fixed logic circuitry), manual processing, or anycombination thereof. Some operations of the example methods may bedescribed in the general context of executable instructions stored oncomputer-readable storage memory that is local and/or remote to acomputer processing system, and implementations can include softwareapplications, programs, functions, and the like. Alternatively or inaddition, any of the functionality described herein can be performed, atleast in part, by one or more hardware logic components, such as, andwithout limitation, Field-programmable Gate Arrays (FPGAs),Application-specific Integrated Circuits (ASICs), Application-specificStandard Products (ASSPs), System-on-a-chip systems (SoCs), ComplexProgrammable Logic Devices (CPLDs), and the like.

FIG. 3 illustrates example method(s) 300 of battery disconnect safeguardand is described with reference to maintaining continuous power for amobile device when subject to an impending secondary battery disconnectevent due to an impact from the device being dropped. The order in whichthe method is described is not intended to be construed as a limitation,and any number or combination of the described method operations can beperformed in any order to perform a method, or an alternate method.

At 302, components of a mobile device are powered with a secondarybattery as an additional power source to a primary battery that powersthe components of the mobile device. For example, the mobile device 100(FIG. 1) has a primary battery 102 as the power source to power thevarious components of the device, and the mobile device includes asecondary battery 104 that can be switched-in as the alternate oradditional power source to power the components of the device. Themobile device 100 is shown with various configurations of the secondarybattery 104 in FIGS. 1 and 2.

At 304, the charge level of the primary battery is monitored to maintainat least a minimum charge level of the primary battery. For example, thebattery controller 110 of the mobile device 100 monitors the chargelevel of the primary battery 102, and maintains at least a minimumcharge level of the primary battery to enable a switch from thesecondary battery 104 to the primary battery 102 as the power source.

At 306, an acceleration of the mobile device is detected, where thedetected acceleration indicates an impending secondary batterydisconnect event due to the mobile device falling. For example, theaccelerometer 126 that is implemented in the mobile device 100 detectsan acceleration of the mobile device 100, which indicates an impendingsecondary battery disconnect event due to the mobile device falling. At308, a sensor input of the detected acceleration of the mobile device isreceived. For example, the controller logic 120 of the batterycontroller 110 in the mobile device 100 receives a sensor input 122 ofthe detected acceleration of the device from the accelerometer 126(e.g., a sensor 124).

At 310, log data of the detected acceleration is maintained. Forexample, the accelerometer 126 (e.g., a sensor 124) in the mobile device100 may be implemented with the sensor buffer 130 to maintain the logdata of the detected acceleration. Alternatively or in addition, the logdata can be streamed to the memory device 116 of the mobile device 100to maintain the log data as a record of the detected acceleration.

At 312, an enhancement to detecting an acceleration of the device (e.g.,an indication that the device is falling) is a determination made as towhether there is touch contact with the mobile device. For example, thebattery controller 110 of the mobile device 100 can receive a sensorinput 122 from a contact sensor (e.g., a sensor 124) that detects usertouch contact with the device. If touch contact with the mobile deviceis detected (i.e., “Yes” from 312), then the method continues at 302 topower the components of the mobile device with the secondary battery. Adetected touch contact with the mobile device is an indication that thedevice has not been dropped and/or is not falling, such as when a useris holding the device. For example, if the battery controller 110receives a sensor input 122 as detected acceleration of the device fromthe accelerometer 126 (at 308), yet a contact sensor detects user touchcontact with the device, the controller logic 120 of the batterycontroller 110 can determine that an impact is not imminent or pending.

If touch contact with the mobile device is not detected (i.e., “No” from312), then at 314, the secondary battery is switched to the primarybattery as the power source of the mobile device. For example, thecontroller logic 120 initiates the battery switch circuit 118 of thebattery controller 110 to switch from the secondary battery 104 to theprimary battery 102 based on both the detected acceleration of themobile device 100 (at 308) and no detected touch contact with the device(at 312).

FIG. 4 illustrates example method(s) 400 of battery disconnect safeguardand, similar to the method described with reference to FIG. 3, isdescribed with reference to maintaining continuous power for a mobiledevice when subject to an impending secondary battery disconnect eventdue to an impact from the device being dropped. The order in which themethod is described is not intended to be construed as a limitation, andany number or combination of the described method operations can beperformed in any order to perform a method, or an alternate method.

At 402, a device state is monitored and rolling log data is maintained.For example, the battery controller 110 of the mobile device 100monitors the device state based on the sensor inputs 122 from the one ormore sensors 124, such as sensor inputs from the accelerometer 126 thatmay be implemented with the sensor buffer 130 to maintain the log dataof the detected acceleration. Alternatively or in addition, the log datacan be streamed to the memory device 116 of the mobile device 100 tomaintain the log data as a record of the detected acceleration.

At 404, a determination is made as to whether a free-fall of the deviceis detected. For example, the accelerometer 126 that is implemented inthe mobile device 100 detects an acceleration of the mobile device 100,which indicates an impending secondary battery disconnect event due tothe mobile device falling. If a free-fall of the device is not detected(i.e., “No” from 404), then the method continues at 402 to continuemonitoring the device state (e.g., the acceleration state of thedevice). If a free-fall of the device is detected (i.e., “Yes” from404), then at 406, the primary battery is switched to as the powersource of the device. For example, the controller logic 120 initiatesthe battery switch circuit 118 of the battery controller 110 to switchfrom the secondary battery 104 to the primary battery 102 based on thedetected acceleration of the mobile device 100.

At 408, a determination is made as to whether impact of the device hasbeen detected within a set number of seconds. For example, the batterycontroller 110 of the mobile device 100 determines whether an impact ofthe device has occurred based on the accelerometer sensor inputs 122. Ifimpact of the mobile device 100 is not detected within a set number ofseconds (i.e., “No” from 408), then at 410, the secondary battery isswitched to as the power source of the device. For example, the batteryswitch circuit 118 of the battery controller 110 switches from theprimary battery 102 back to the secondary battery 104 if the expectedimpact of the falling device is not detected. If a free-fall of themobile device is detected at 404, but then impact of the device is notdetected at 408, then this would indicate that the device was falling,such as if the device was dropped, but then recovered before impact withthe ground. The method then continues at 402 to continue monitoring thedevice state (e.g., the acceleration state of the device).

If impact of the mobile device 100 is detected within the set number ofseconds (i.e., “Yes” from 408), then at 412, a determination is made asto whether the drop and battery contact bounce of the device afterimpact has completed. For example, the battery controller 110 of themobile device 100 determines whether the drop and battery contact bounceof the device after impact has completed based on the accelerometersensor inputs 122 (e.g., approximately zero acceleration). If thecontact bounce of the device has not completed after the fall and impact(i.e., “No” from 412), then at 414, the device continues to be monitoredand the drop and contact bounce determination is repeated at 412, asimplemented by the battery controller 110 of the mobile device 100. Ifthe contact bounce of the device has completed after the fall and impact(i.e., “Yes” from 412), then at 410, the secondary battery is switchedto as the power source of the device and the method then continues at402 to continue monitoring the device state.

FIG. 5 illustrates various components of an example device 500 in whichembodiments of battery disconnect safeguard can be implemented. Theexample device 500 can be implemented as any of the computing devicesdescribed with reference to the previous FIGS. 1-4, such as any type ofclient device, mobile phone, tablet, computing, communication,entertainment, gaming, media playback, and/or other type of device. Forexample, the mobile device 100 shown in FIG. 1 may be implemented as theexample device 500.

The device 500 includes communication transceivers 502 that enable wiredand/or wireless communication of device data 504 with other devices.Additionally, the device data can include any type of audio, video,and/or image data. Example transceivers include wireless personal areanetwork (WPAN) radios compliant with various IEEE 802.15 (Bluetooth™)standards, wireless local area network (WLAN) radios compliant with anyof the various IEEE 802.11 (WiFi™) standards, wireless wide area network(WWAN) radios for cellular phone communication, wireless metropolitanarea network (WMAN) radios compliant with various IEEE 802.15 (WiMAX™)standards, and wired local area network (LAN) Ethernet transceivers fornetwork data communication.

The device 500 may also include one or more data input ports 506 viawhich any type of data, media content, and/or inputs can be received,such as user-selectable inputs to the device, messages, music,television content, recorded content, and any other type of audio,video, and/or image data received from any content and/or data source.The data input ports may include USB ports, coaxial cable ports, andother serial or parallel connectors (including internal connectors) forflash memory, DVDs, CDs, and the like. These data input ports may beused to couple the device to any type of components, peripherals, oraccessories such as microphones and/or cameras.

The device 500 includes a processing system 508 of one or moreprocessors (e.g., any of microprocessors, controllers, and the like)and/or a processor and memory system implemented as a system-on-chip(SoC) that processes computer-executable instructions. The processorsystem may be implemented at least partially in hardware, which caninclude components of an integrated circuit or on-chip system, anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA), a complex programmable logic device (CPLD), and otherimplementations in silicon and/or other hardware. Alternatively or inaddition, the device can be implemented with any one or combination ofsoftware, hardware, firmware, or fixed logic circuitry that isimplemented in connection with processing and control circuits, whichare generally identified at 510. The device 500 may further include anytype of a system bus or other data and command transfer system thatcouples the various components within the device. A system bus caninclude any one or combination of different bus structures andarchitectures, as well as control and data lines.

The device 500 also includes computer-readable storage memory 512 thatenable data storage, such as data storage devices that can be accessedby a computing device, and that provide persistent storage of data andexecutable instructions (e.g., software applications, programs,functions, and the like). Examples of the computer-readable storagememory 512 include volatile memory and non-volatile memory, fixed andremovable media devices, and any suitable memory device or electronicdata storage that maintains data for computing device access. Thecomputer-readable storage memory can include various implementations ofrandom access memory (RAM), read-only memory (ROM), flash memory, andother types of storage media in various memory device configurations.The device 500 may also include a mass storage media device.

A computer-readable storage memory 512 provides data storage mechanismsto store the device data 504, other types of information and/or data,and various device applications 514 (e.g., software applications). Forexample, an operating system 516 can be maintained as softwareinstructions with a memory device and executed by the processing system508. The device applications may also include a device manager, such asany form of a control application, software application,signal-processing and control module, code that is native to aparticular device, a hardware abstraction layer for a particular device,and so on. In this example, the device 500 includes a battery controller518 that implements embodiments of battery disconnect safeguard, and maybe implemented with hardware components or in software, such as when thedevice 500 is implemented as the mobile device 100 described withreference to FIGS. 1-4. An example of the battery controller 518 is thebattery controller 110 that is implemented by the mobile device 100.

The device 500 also includes sensors 520 that input sensor data to thebattery controller 518. The sensors 520 may be implemented as any one orcombination of an accelerometer, gyro, touch contact sensors, a moisturedetector, temperature detector, and/or any other type of environmentalcondition sensors, as described with reference to the sensors 124 shownin FIG. 1. Additionally, any one or more of the sensors 520 may bepositioned in the device, in an accessory (e.g., in a device protectivecover), or both in the device and in a cover.

The device 500 also includes an audio and/or video processing system 522that generates audio data for an audio system 524 and/or generatesdisplay data for a display system 526. The audio system and/or thedisplay system may include any devices that process, display, and/orotherwise render audio, video, display, and/or image data. Display dataand audio signals can be communicated to an audio component and/or to adisplay component via an RF (radio frequency) link, S-video link, HDMI(high-definition multimedia interface), composite video link, componentvideo link, DVI (digital video interface), analog audio connection, orother similar communication link, such as media data port 528. Inimplementations, the audio system and/or the display system areintegrated components of the example device. Alternatively, the audiosystem and/or the display system are external, peripheral components tothe example device.

The device 500 can also include one or more power sources 530, such aswhen the device is implemented as a mobile device. The power sources mayinclude a charging and/or power system, and can be implemented as aflexible strip battery, a rechargeable battery, a chargedsuper-capacitor, and/or any other type of active or passive powersource.

Although embodiments of battery disconnect safeguard have been describedin language specific to features and/or methods, the subject of theappended claims is not necessarily limited to the specific features ormethods described. Rather, the specific features and methods aredisclosed as example implementations of battery disconnect safeguard,and other equivalent features and methods are intended to be within thescope of the appended claims. Further, various different embodiments aredescribed and it is to be appreciated that each described embodiment canbe implemented independently or in connection with one or more otherdescribed embodiments.

1. A system, comprising: a primary battery configured as a power sourceto power components of a mobile device; a secondary battery configuredas an additional power source to power the components of the mobiledevice; and a battery controller configured to switch from the secondarybattery to the primary battery as the power source based on a detectedfree-fall of the mobile device.
 2. The system as recited in claim 1,wherein the detected free-fall indicates an impending secondary batterydisconnect event.
 3. The system as recited in claim 1, furthercomprising an accelerometer configured to register the free-fall of themobile device as acceleration, and wherein the battery controller isconfigured to receive a sensor input of the acceleration from theaccelerometer.
 4. The system as recited in claim 1, wherein thesecondary battery is one of: integrated within the mobile device;integrated in a removable housing cover of the mobile device; connectedto contacts that are integrated in a housing of the mobile device;integrated in a protective cover or case for the mobile device; orexternal to the mobile device.
 5. The system as recited in claim 1,wherein the battery controller is configured to: monitor a charge levelof the primary battery; and maintain at least a minimum charge level ofthe primary battery to enable the switch from the secondary battery tothe primary battery as the power source.
 6. The system as recited inclaim 1, wherein the battery controller is implemented with hardwarecomponents configured to receive an indication of the detected free-falland switch from the secondary battery to the primary battery.
 7. Thesystem as recited in claim 1, further comprising a memory and processingsystem to implement the battery controller as software that isconfigured to receive an indication of the detected free-fall and switchfrom the secondary battery to the primary battery.
 8. The system asrecited in claim 1, further comprising a memory configured to maintainlog data of the detected free-fall, wherein the log data is one ofbuffered in the memory on an accelerometer configured to detectacceleration of the mobile device, or streamed to the memory in themobile device to maintain the log data.
 9. The system as recited inclaim 1, further comprising one or more contact sensors configured todetect touch contact with the mobile device, and wherein the batterycontroller is configured to switch from the secondary battery to theprimary battery based on the detected free-fall of the mobile devicebeing dropped.
 10. A method, comprising: powering components of a mobiledevice with a secondary battery as an additional power source to aprimary battery that is configured to power the components of the mobiledevice; detecting an impending impact of the mobile device due to beingdropped causing an impending secondary battery disconnect event; andswitching from the secondary battery to the primary battery as the powersource of the mobile device based on the detected impending impact. 11.The method as recited in claim 10, further comprising: switching backfrom the primary battery to the secondary battery based on a lack ofacceleration of the mobile device.
 12. The method as recited in claim10, further comprising: receiving a sensor input of acceleration of themobile device from an accelerometer that registers the impending impactof the mobile device as the acceleration.
 13. The method as recited inclaim 10, further comprising: monitoring the charge level of the primarybattery; and maintaining at least a minimum charge level of the primarybattery to enable said switching from the secondary battery to theprimary battery as the power source.
 14. The method as recited in claim10, further comprising: maintaining log data of the detected impendingimpact, wherein the log data is one of buffered in memory of anaccelerometer configured to detect acceleration of the mobile device, orstreamed to device memory that maintains the log data.
 15. The method asrecited in claim 10, further comprising: detecting a lack of touchcontact with the mobile device; and said switching from the secondarybattery to the primary battery based on the detected impending impact ofthe mobile device being dropped.
 16. A mobile device, comprising: abattery configured as a power source to power components of the mobiledevice; a sensor configured to detect a free-fall of the mobile devicebased on acceleration indicating the mobile device being dropped; and abattery controller configured to switch the power source of the mobiledevice based on the detected free-fall of the mobile device, the powersource switched to maintain power for the components of the mobiledevice.
 17. The mobile device as recited in claim 16, wherein: thesensor is an accelerometer configured to register the free-fall of themobile device as the acceleration; and the battery controller isconfigured to receive a sensor input of the acceleration from theaccelerometer.
 18. The A mobile device as recited in claim 16, wherein:the battery is a secondary battery configured as an additional powersource to power the components of the mobile device; the batterycontroller is configured to: switch from the secondary battery to aprimary battery as the power source based on the detected free-fall ofthe mobile device; and switch back from the primary battery to thesecondary battery as the power source based on a lack of theacceleration of the mobile device.
 19. The mobile device as recited inclaim 18, wherein the battery controller is configured to: monitor acharge level of the primary battery; and maintain at least a minimumcharge level of the primary battery to enable the switch from thesecondary battery to the primary battery as the power source.
 20. Themobile device as recited in claim 16, further comprising one or morecontact sensors configured to detect touch contact with the mobiledevice, and wherein the battery controller is configured to switch thepower source of the mobile device based on the detected free-fall of themobile device being dropped.